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    <title>Document</title>
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    <script>
        // var age = parseInt(prompt('请输入你的年龄'));

        // if(age>=18){
        //     console.log('欢迎光临');
        // }else{
        //     // 如果if后边的()最后的结果是false 那就走进
        //     // else后边的大括号
        //     console.log('好好学习天天向上');
        // }

        var year = parseInt(prompt('请输入年份'));

        // var res = (year % 4 == 0) &&   (year % 100 != 0)  || (year % 400 == 0)
        // console.log('您输入的年份'+year+res+'闰年');

        if((year % 4 == 0) &&   (year % 100 != 0)  || (year % 400 == 0)){
            console.log('您输入的年份'+year+'是闰年');
        }else{
            console.log('您输入的年份'+year+'不是闰年');
        }
    </script>
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